A composite refers to a material consisting of two or more individual constituents. A reinforcing constituent is embedded in a resin matrix to form the composite. Common composites are composed of glass or carbon fibers in a plastic resin. Natural fibers can also be used. Resins can be of the form of thermoset or thermoplastic materials which each have their own unique properties. Epoxy resins are also used for fiber reinforced composites. The resin matrix is usually formed of a resin and a curing agent. Polyamines, such as diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and ethyleneamine, can be used as curing agents for such resins. There is, however, a need for more sustainable and bio-based resin matrixes for reducing the use of petroleum based resins.
Lignin has previously been used in fiber reinforced resin composites for replacing part of e.g. the epoxy resin used. The inventors have, however, recognized the need for a more environmentally friendly fiber mat reinforced resin composite having properties suitable for further applications and for a method for producing such a composite.